A verb for “to try” based on the root √NDEB in notes from the 1960s (PE17/167). As suggested by Christopher Gilson, this appears to be a draft of Tolkien’s attempt to define the phrase “try harder” in Quenya. Of the root √NDEB, Tolkien said it “too obviously = endeavor”, and he wrote another root √RIK below it, with Quenya verb forms rike or rihta. It seems Tolkien here changed √NDEB >> √RIK, but in later notes from 1969 Tolkien had the root √NDAB “endeavor, try, seek opportunity” with a Quenya verb form nauva “will try” (PE22/151), indicating that the concept of √NDEB was not entirely abandoned.
Neo-Quenya: For purposes of Neo-Quenya, I would mainly use ric- for “to try (put forth effort)”, but I think nev- is worth retaining with a different connotation: “to try, ✱seek opportunity, experiment”. In other words, you use ric- “try” when you are uncertain whether you are capable of performing the action, and nev- “try” when you know you are capable, but are uncertain what the result of the action will be. I prefer nev- over the 1969 form ✱nav- because it has a Sindarin cognate S. dev-.
In 2024-08-19 post on the Vinyë Lambengolmor Discord Server (VLDS), Luinyelle suggested this verb might be used with an adverb to describe someone’s approach to a task or situation, roughly equivalent to English “take” in phrases like “take something seriously”. For example: néves i hrangwe lungo “he tried the problem serious[ly] (with seriousness)” = English “he took the problem seriously”.
#nav- vb. "judge" (cited in the form navë, apparently the 3rd person aorist). Also given with pronominal suffixes: navin *"I judge" (Tolkien's free translation: "I think"), navilwë "we judge" (VT42:33, 4, VT48:11)